The destruction wrought by Cyclone Idai in southern Africa this month shows weather warnings must spur action and infrastructure has to be built with climate risks in mind if people are to be kept safe on a warming planet.

Cyclone Idai’s deadly hit has left some 1.85 million people in need of assistance in Mozambique in a catastrophe that United Nations chief Antonio Guterres said on Tuesday rang “yet another alarm bell” about climate change.